Extendable and retractible material delivery devices

ABSTRACT

An extendible and retractible boom or conduit comprises a number of shaft or boom members on a common longitudinal axis, each except the outermost member being telescoped within the one next adjacent. Each telescoped member has a piston slidably sealed to the inner wall of the next adjacent outer member to form a series of tandem-arranged sealed pistons. Fluid passageways are provided between adjacent shaft members so that fluid supplied under pressure to a port of the device flows through the passageways to all the piston heads, thereby extending the telescoped shaft members and at the same time driving fluid out from under each piston through fluid passageways to another port of the device. When the pressurized fluid flow is reversed to send pressurized fluid to the under sides of the pistons, the telescoped members are retracted and fluid above the pistons is driven out through the first-mentioned port. A conduit for conveying fluid or other material enters the device above the piston heads and tubular members attached to one or more of the pistons move with the pistons to effectively extend the length of the conveying conduit when the piston members are extended. Thus, the material or fluid can be ejected from the delivery end regardless of the length of extension of the device. In another embodiment, a second material or fluid conveying conduit, also extendible and retractible with the extension and retraction of the device, is adapted to retrieve the material or fluid delivered through the other conduit, such as for example in the case of earth drilling or well drilling operations where fluid may be forced down to the drilling member and then retracted and recirculated.

United States Patent [191 Russell, Jr.

[ Nov. 18, 1975 1 1 EXTENDABLE AND RETRACTIBLE MATERIAL DELIVERY DEVICES[76] Inventor: Wayne B. Russell, Jr., 3895 Lugo Ave., Lynwood, Calif.90262 22 Filed: Sept. 5, 1974 21 Appl. No.: 503,287

Related US. Application Data [63] Continuation-in-part of Ser. No.418,073, Nov. 21, 1973, which is a continuation of Ser. No. 177,592,Sept. 3, 1971, abandoned.

[52] US. Cl. 173/79; 92/52; 92/53; 92/80; 92/31 [51] Int. Cl. B25D17/14; E21C 7/00 [58] Field of Search 92/51, 52, 53, 62, 65, 92/108,112, 80, 31; 173/79; 64/23 [56] References Cited UNITED STATES PATENTS1,626,277 4/1927 Gartin 173/79 X 1,908,734 5/1933 Cuthill 173/79 X2,288,545 6/1942 Osgood 173/79 X 3,180,236 4/1965 Beckett 92/177 X3,603,207 9/1971 Parrett 92/108 X 3,610,100 10/1971 Hoffman... 92/108 X3,696,712 lO/l972 Sung 92/52 3,768,578 10/1973 Russell, Jr 92/53 X3/1974 Klein 92/52 X Primary E.\-aminerMartin P. Schwadron AssistantExaminer-Abraham Hershkovitz Attorney, Agent, or FirmDonald D. Mon

[ ABSTRACT An extendible and retractible boom or conduit comprises anumber of shaft or boom members on a common longitudinal axis, eachexcept the outermost member being telescoped within the one nextadjacent. Each telescoped member has a piston slidably sealed to theinner wall of the next adjacent outer member to form a series oftandem-arranged sealed pistons. Fluid passageways are provided betweenadjacent shaft members so that fluid supplied under pressure to a portof the device flows through the passageways to all the piston heads,thereby extending the telescoped shaft members and at the same timedriving fluid out from under each piston through fluid passageways toanother port of the device. When the pressurized fluid flow is reversedto send pressurized fluid to the under sides of the pistons, thetelescoped members are retracted and fluid above the pistons is drivenout through the first-mentioned port. A conduit for conveying fluid orother material enters the device above the piston heads and tubularmembers attached to one or more of the pistons move with the pistons toeffectively extend the length of the conveying conduit when the pistonmembers are extended. Thus, the material or fluid can be ejected fromthe delivery end regardless of the length of extension of the device. Inanother embodiment, a second material or fluid conveying conduit, alsoextendible and'retractible with the extension and retraction of thedevice, is adapted to retrieve the material or fluid delivered throughthe other conduit, such as for example in the case of earth drilling orwell drilling operations where fluid may be forced down to the drillingmember and then retracted and recirculated,

15 Claims, 9 Drawing Figures US. Patent Nov. 18, 1975 Sheet 1 of63,920,084

K V l US. Patfint Nov. 18,1975 Sheet20f6 3,920,084

US. Patent Nov. 18, 1975 Sheet 3 of6 3,920,084

US. Patent Nov. 18,1975 Sheet4of6 3,920,084

US. Patent Nov. 18, 1975 Sheet 6 of6 3,920,084

EXTENDABLE AND RETRACTIBLE MATERIAL DELIVERY DEVICES This is acontinuation-in-part of application Ser. No. 418,073 filed Nov. 21, 1973as a continuation of application Ser. No. 177,592 filed Sept. 3, 1971now abandoned.

This invention relates to extendible and retractible material deliveryequipment, and more particularly to such equipment capable of beingextended linearly from a relatively short length to a substantiallygreater length and being contracted or retracted to its minimum length.

In my said co-pending US. Pat. application Ser. No. 418,073 there isshown and claimed a shaft or boom arrangement especially adapted forproviding rotational torque for earth drilling purposes. The shaft orboom comprises a number of telescoped members within an outer member,each telescoped member having a piston slidably sealed to the inner wallof the next adjacent outer member to form a series of tandem-arrangedsealed pistons. Fluid passageways are provided between adjacent shaftmembers and a pair of fluid ports are provided through the outer memberso that pressurized fluid may be sent into one of the ports and causedto flow through the system so that the pressurized fluid is applied toall the pistons in the direction which telescopically extends each shaftmember relative to the next outer shaft member, in the direction whichextends the length of the shaft. When the direction of fluid pressure isreversed so that the pressurized fluid flows into the other of theports, the pressurized fluid is applied to the under side of each of thepistons so that each shaft member which is within another member slidesin the direction which contracts the overall length of the shaft or boomtoward its minimum length.

In my co-pending US. Pat. application Ser. No. 494,196 filed Aug. 2,1974 there are also shown shaft or boom arrangements having multipletelescoped members which are extendible and retractible and may berotated.

In Soderstrom US. Pat. No. 3,705,083 issued Mar. 29, 1955 there is alsoshown an extendible and contractible telescoped shaft arrangement, whichhowever is not adapted for rotational torque.

It is an object of the present invention to provide conduit means forthe delivery of material through a boom or shaft which is extendible andretractible so that the arrangement can be used to deliver the materialat any distance from the material loading end of the shaft, which liesbetween the minimum and maximum length of the boom or shaft.

The invention is carried out by utilizing an extendible and retractibleboom or shaft arrangement of the general type noted above to which thereis attached a material conveying conduit extending into the casing ofthe device. The piston members of the device are provided with one ormore members which telescope relative to the material conveying conduit,and can slide longitudinally relative to the conduit. Material conveyingconduit means related to the piston members increases the effectivelength of the said conduit when the piston members are extended. At theend of the ma terial conveying conduit means opposite the loading end ofthe said conduit there is provided a delivery opening through whichmaterial introduced into the conduit at the loading end is expelled.

In one embodiment of the invention no provision is made for returning orrecirculating the delivered material.

In another embodiment provision involving the use of two conduits ismade for ejecting the delivered material and returning it to a positionnear the loading end, or recirculating it.

According to an optional feature, provision is made for rotating theshaft or boom members so that the device can be used where rotation isrequired, such as for example for a drill Kelly on which an auger drillwill be attached to the extendible shaft. In such case, it is oftendesirable to supply lubrication such as water or mud to the drill, whichmay be done by use of the delivery conduit or conduits. In sucharrangements it is often desired to collect or recirculate the liquid ormud delivered to the drill, in which case the embodiment providing forcollection of the ejected material may be used.

According to another objectional arrangement no provision is providedfor rotation, in which case the device may act as a non-rotatingextendible boom capable of delivery material.

Devices according to this invention have many uses other than in a drillKelly as will become apparent from the following description.

The foregoing and other features and aspects of the invention will bebetter understood from the following detailed description and theaccompanying drawings of which:

FIG. 1 is an elevation view, partly in cross-section taken at line l1 ofFIG. 2 and line la-la of FIG. 3, of a rotatable multi-stage extendibleand retractible material delivery device according to this invention;

FIG. 2 is a cross-section view taken at line 22 of FIG. 1;

FIG. 3 is a cross-section view taken at line 33 of FIG. 1;

FIG. 4 is an elevation view, partly in cross-section taken at line 44 ofFIG. 5, and line 4a4a of FIG. 6, showing a rotatable material deliverydevice somewhat similar to that of FIG. 1 but differing from FIG. 1 inhaving provision for return or circulating flow of the material;

FIG. 5 is a cross-section view taken at line 5--5 of FIG. 4;

FIG. 6 is a cross-section view taken at line 6-6 of FIG. 4;

FIG. 7 is an elevational cross-section view of an injection devicesomewhat similar to that of FIG. 1 but without provision for rotationaldrive;

FIG. 8 is a cross-section view taken at line 8-8 of FIG. 7; and

FIG. 9 is an end view looking from line 99 of FIG. 7.

Referring to FIGS. 1, 2 and 3 there is shown a multistage extendible andretractible shaft or boom arrangement adapted to be driven in rotationand provided with conduit means for delivering material. The arrangementis adapted for any of a number of uses, one of which is as a Kelly drivein an earth drilling operation. It is shown extendible in a downwarddirection which will be its normal position for earth drilling, but itshould be understood that it is capable of uses other than earthdrilling and may be used in other positions than that shown in FIG. 1.The mechanism comprises a stationary outer cylindrical or tubular shaftmember 10 concentric with a longitudinal axis 9 and provided with aclosure 11 at the top. At the lower part of member 10 its structure isbrought outward at position 12 to form an outwardly extending gearhousing 13 having an internal cavity 14 containing a pinion 15 fastenedto a vertical shaft 16 extending upwardly through the upper wall ofhousing 13 and attached to the shaft of a motor 17 mounted on the uppersurface of gear housing 13, which drives the pinion. The member 10 andthe gear housing will be held stationary by mounting on a suitable bedor frame represented at 18, for example the platform of a drill rig whenused for drilling. Within the section 12a outstanding from the tubularmember 10 and within the gear housing there is a member 19 having anouter cylindrical surface concentric with axis 9, adapted for rotationrelative to cylindrical member 10 and the gear housing, by provision ofbearings 20 and .21 positioned between the gear housing and cylinder 19.These bearings are of a conical type adapted to withstand radial forcesand also longitudinal thrust. There is attached to the outer cylindricalsurface of member 19 a gear 24 which meshes with pinion 15 so thatrotation of the motor 17 rotates member 19 relative to tubular member10. Seals 22 and 23 serve to prevent the escape of oil from the cavity14 of the gear housing, which is ordinarily present to lubricate thegears and bearings. A large extent of the inner surface of member 19 isformed in the shape of a square 19a, as best seen in FIGS. 1 and 2.

A cylindrical piston 25 is placed concentrically within cylindricalmember 10 near the upper end of member 10 and is free to slidelongitudinally with an annular seal 51 relative to member 10. Piston 25comprises a member 25 which extends inwardly to a conical bearing 27placed between the member 25 and another portion 250 of the piston,having attached to it an annular disc-like portion 26 having an outerperiphery substantially at the inner cylindrical surface of member 10.The under surface of member 26 is attached to the upper end of a shaftor boom member which is double-walled at its corners as best seen inFIG. 3.

There is fixed within the cylindrical member 10 a cylindrical or tubularconduit 28 fixed relative to member 10 by being fastened to closure 11.The conduit 28 is concentric with the cylindrical side of member 10 andis co-axial with the longitudinal axis 9. The conduit 28 extends from aposition above the closure 11 and passes down through the cylindricalmember 10 to a position approximately in the region of the lower part ofthe gear housing 13.

There is attached to the portion 25a of piston 25, an annular pistonportion 25b located between the annular portion 250 and the outercircumference of conduit 28. This portion 25b is provided with aninternal annular groove 29 in which there is placed an annular seal 31which seals the piston portion 25b to the tube 28 while permittinglongitudinal sliding of the piston member 25b relative to the conduit. Acylindrical or tubular member 32 is integrally attached to the pistonportion 25b, this cylindrical member being concentric with the conduit28 and spaced from the outside surface of the conduit.

Although the bearing 27 permits relative rotation between piston members25 and 25a, the bearing nevertheless holds piston members 25 and 25atogether so that no relative longitudinal movement is permitted betweenthe two portions 25 and 25a. The seals 51 and .31, however, permit theentire piston consisting of parts 25 25a and 25b to slide longitudinallyrelative to outer cylinder 10 and the conduit 28 so that the shaftmember 30 and the cylinder 32, attached to the piston,

can move longitudinally with the piston.

Beneath the piston portion 26 and between the members 30 and 32 there islocated a second piston head 33 sealed to the inner cylindrical wall30bof member 30 by a seal 34, and to the cylinder 32 by a seal 35. Thereis attached to piston head 33 a shaft or boom member 36 concentric withaxis 9. Member 36 is double-walled at its corners, comprising outer wall36a and inner wall 36b. Within the inner wall 36b and spaced at somedistance from wall 36b there is an inner cylindrical wall 37 concentricwith axis 9 and attached to piston head 33.

In the annular space between walls 36b and 37 and beneath piston head 33there is a third piston 38 sealed to inner wall 36b by a seal 39 and tothe wall 37 by a seal 40. A cylindrical member 41 attached to pistonhead 38 is co-axial with axis 9 and spaced between wall 36b and wall 37.

It is recognized from the foregoing description that piston 25 isslidable with its member 30, longitudinally relative to the fixed casing10 so that the lower end of the member 30 can be extended downwardbeyond the member 19. Likewise piston 33 with its member 36 and innermember 37 is slidable downward relative to piston 25 so that the members36 and 37 can be projected downward beyond the lower end of member 30.Similarly, the piston 38 can be moved downward relative to piston 33 andits member 41 thus extended well beyond the lower end of member 36.

At its lower end, the member 30 is formed as a solid square portion 300of which both the inner and outer surfaces are square as best seen inFIGS. 1 and 2, at the upper end of which the doubled walls 30a and 30bterminate. Likewise, at its lower end the wall 36 is formed as a solidsquare section 36c of which both the inner and outer walls are square,as can be seen in FIGS. 1 and 2. The outer surface of wall 41 is formedas a square 41a and its inner wall is formed as a cylinder 41b as can beseen in FIGS. 2 and 3. The dimensions of the squares 19a, 30c, 36c and41a are such that the dimension of each outer square surface conformswith the dimension of the square inner surface of the next outer'member, so that member drives member 300 which in turn drives member 36cwhich in turn drives member 41a, in rotation when the motor 17 isrunning. Hence, it is seen that the members 30, 36 and 41 are not onlyslidable longitudinally to be extended as a shaft or boom but alsorotate in unison so that the entire extended shaft or boom is rotatable.To facilitate the slidability, there is provided a seal 42 betweensquare 30c and 360 and a seal 43 between squares 36c and 41a.

The lower end of member 41 is provided with a closure 44 through whichthere is a concentric opening 45 aligned with axis 9 and conduit 28 sothat material which may be injected into the upper end of tube 28 canexit through opening 45 in any position of retraction or extension ofthe extendible members.

For the purpose of extending and retracting the mechanism there isprovided a hydraulic system. This comprises a fitting or port 52 throughthe upper end of the casing wall 10 which communicates with region 53above the piston 25 so that an inlet conduit 54 connected to the fitting52 can supply hydraulic fluid under pressure above piston 25. Theconical bearing 27 is of a type which provides a passageway 55 providingcommunication between region 53 and a space 56 between members 25 and26. A passageway 57 through the piston member 26 communicates betweenspace 56 and a I space 58 between pistons 25 and 33. A passageway 59through piston 33 provides communication between space 58 and a space 60between piston heads 33 and 38.

A fitting or port 61 near the lower end of casing provides communicationfrom the exterior to the space 62 between casing 10 and outer wall 30aof the doublewall member 30. Ports 63 communicate between region 62 andthe spaces 64 between walls 30a and 3012. At the lower end of wall 30bthere are provided through it ports 65 providing communication betweenspaces 64 and space 66 between member 30 and 36. At the upper end ofwall 36a there are ports 67 providing communication between space'66 andthe spaces 68 between walls 36a and 36b. At the lower end of wall 36bthere are provided ports 105 between spaces 68 and the space 106 betweenwalls 36b and 41.

The hydraulic fluid for expanding and retracting the boom or shaft iscontained in a tank 70 shown in phantom from which a conduit 71 shown insingle-line form connects with conduit 54, and another conduit 72communicates between the tank and conduit 73 attached to fitting 61. Apump 74 serves to pump fluid from the tank either in the direction ofarrow 75 or arrow 76 depending on the setting of the pump. Assuming thepump is set to force hydraulic fluid in the direction of arrow 75, thefluid enters through fitting 52 to region 53 from where it entersregions 58 and 60 to force the pistons and their shaft members to slidedownward as shown in FIG. 1 to extend the shaft members which may act asa shaft or boom. Fluid in the system during this expansion is therebyforced out through fitting 61 and back to the tank in the direction ofarrow 77. When it is desired to retract the cylinders the pump is set toforce fluid from the tank in the direction of arrow 76 through fitting61 and into region 62 below piston 25. The fluid flows through ports 63into regions 64 from whence it flows through the ports 65 into region 66and then through ports 67 into regions 68 from where it flows throughports 105 into region 106 below piston 38. The force of the hydraulicfluid flow in this direction pushes all the piston heads and their shaftmembers upward toward the top closure 11 to the retracted position shownin FIG. 1, and fluid located above the pistons is thereby forced out ofthe casing through fitting 52 and back to the tank in the direction ofarrow 79.

When the shaft or boom is extended the conduit members 32 and 37 aresimilarly extended because of their attachment to the respective pistons25 and 33. Thus the conduit 28 is extended by the members 32 and 37,which in order to prevent leakage of material between the conduitmembers or sections, are provided with the respective seals 31 and 35.Regardless of what position the pistons and their shaft members are inrespect to extension or retraction, any fluid or material sent into thetop of conduit 28 will be forced out through opening 45.

Such a system can have many uses, an important one which is as an earthdrilling equipment in which liquid or mud or the like is supplied to thedrilling area. In such case a suitable drilling bit or auger will beattached at the lower end of cylinder or shaft member 41 in a well-knownmanner to perform the drilling by useof the motor 17 to rotate theauger. During the drilling operation the fluid material may be forceddown through conduits 28, 32 and 37 and out through opening 45 to theregion of the drilling.

The embodiment shown in FIGS. 4, 5 and 6 is also equipped with anextendible boom arrangement and with means for rotating it. It has amaterial injection arrangement which differs from that shown in FIGS. 1,2 and 3 in that provision is made for collecting the material which isinjected, which is advantageous in some uses such as for example inearth drilling where it is desired to inject fluid or mud or the like tothe drilling region and then withdraw it from that region. Thearrangement comprises a cylindrical casing 10a provided with an upperclosure 1 1a, a gear housing 13a in which there is a pinion 15a drivableby a motor 17a, which drives a gear 24a mounted on the periphery of arotat able cylindrical member 19a rotatable relative to the gear housingby bearings 20a and 21a, in a manner analogous to corresponding partsshown in FIGS. 1 to 3. In a manner analogous to FIG. 1, there is apiston 25a within the cylinder 10a having attached to it a double-walledmember 30 and also to a cylindrical member 32. The members 30 and 32 areadapted to rotate relative to piston member 25a by means of a conicalbearing 27a, and the piston is adapted to slide longitudinally relativeto casing 10a. A second piston member 35a attached to a cylindricalmember 41a is located below the piston 25a. A fitting 52a communicateswith space 53a above piston 25 a and afitting 61a communicates withregion 62a.

It will be recognized that this piston arrangement comprising twopistons within thecasing, operates in a manner analogous to thethree-piston arrangement shown in FIG. 1. When hydraulic fluid from tank700 is forced through fitting 52a through conduit 71a into region 53aabove piston 25a, this fluid passing through duct 27 of the bearing 27aand on through passageway 59a to the region above piston 35a, forces thetwo pistons downward relative to the casing and to each other to extendthe boom or shaft in a manner analogous to that described in connectionwith FIG. 1. To retract the extended boom or shaft the hydraulic fluidis forced through conduit 72a and fitting 61a to region 62a so that itflows through ducts 67a to the spaces between the double walls of member30 from where it flows through ducts 65a into the space between members30 and 41a, thereby forcing both pistons to retract to their positionshown in FIG. 4.

Rotation of the boom or shaft is provided in a manner similar to thatshown in FIGS. 1 to 3, namely by means of squared members 19a, 30c andthe squared periphery 4111 The material injection system in theembodiment of FIGS. 4, 5 and 6 comprises a double-walled cylindricalconduit comprising an outer wall 81 and an inner wall 82 spaced withinthe outer wall to leave an annular space 83 between them. The walls ofthis conduit are concentric with the members 30 and 41a and with thecentral longitudinal axis 9a. The walls of member 80 are fixed to theupper closure 11a and the space 83 between them communicates with aspace 84 within a manifold 85 having a port or opening 86 for flow ofmaterial. The lower end of space 83 communicates with a region 87 aboveclosure 44a attached to the lower end of cylindrical member 41a. Anopening 88 through closure 44a serves to pass material flowing throughconduit 80.

Within the wall 82 there is slidably fitted a cylindrical conduit member90, open at both ends, and provided at its upper end with an outwardlyextending flange 91 having a peripheral recess 92 containing an annularseal 93 for slidably sealing the cylinder 90 to the wall 82. At thelower end of cylinder 90 there is provided an inwardly extending flange94 having a recess 95 containing an annular seal 96 which slidably sealsthe cylinder to an inner cylindrical conduit member 97 concentric withconduit member 90 and with axis 9a and attached at its lower end to theclosure 44a. The upper end of conduit 97 is provided with an outwardlyextending flange 98 having a recess 99 within which is placed an annularseal 100 which slidably seals conduit member 97 within the inner wall ofconduit 90. Aligned with axis 9a and with the opening through cylinder97 the closure member 11 is provided with an opening 101 which providesaccess to the interior of cylinder 97. At the lower end of cylinder 97the closure 44a is provided with an opening 102 through which materialmay pass through the cylinder 97.

From the foregoing description it is seen that the pistons a and 350 maybe extended hydraulically until the outer portion of piston member 250reaches the upper shoulder of cylinder 19a and the outer part of piston35a reaches the upper shoulder of square section 50c. The slidingmovement of the cylindrical member 41a whose closure 44a is attached tocylindrical member 97, will cause member 97 to slide longitudinally withit. When the lower part of the flange 98 reaches the upper part offlange 94, the continued sliding extension of cylinder 97 will now causecylinder 90 to slide accordingly. Similarly, retraction of the piston35a to its position shown in FIG. 4 will cause corresponding retractionof cylinders 97 and 90 to their positions BhOVWI in FIG. 4. When rotarymotion is applied to the cylinders of the pistons by motor 17a, thisrotation will be applied through closure 44a to the inner most cylinder97, and this rotary movement may or may not be transmitted to thecylinder 90 depending on relative amounts of friction at its seals.Relative rotation of the cylinders 90 and 97 is not required for theiroperation as their function is the transfer of material through them.

From the foregoing description it is recognized that at any degree ofextension or retraction of the pistons and cylinders, material such asfluid may be delivered or recovered through the injection cylinders.This can be useful in applications such as earth drilling wherematerial, ordinarily of a fluid character such as mud or water can besent either into port 86 or port 101 and recovered through the otherport. Normally the delivery will be through the central portion 101which will deliver the material through opening 102, in which case therecovery will be through port 88 and from where it will flow out throughport 86.

FIGS. 1 through 6 show arrangements for injecting material, having arotational drive capability. It is not essential, however, to providerotational drive in order to inject or deliver material. FIGS. 7 through9 show an arrangement for material delivery wherein no rotational driveis provided. The arrangement in FIGS. 7 to 9 is similar to that shown inFIGS. 1 through 3 in that provision is made for material delivery butnot for material return or recirculation. It will be understood howeverthat a non-rotational system analogous to that of FIGS. 4 through 6could be provided wherein there is provision for return or recirculationof the material.

In FIGS. 7 through 9, numerals similar to those used in FIGS. 1 through3 generally indicate analogous parts excepting that in FIGS. 7 through 9the subscript b is generally provided. The arrangement comprises acylindrical or tubular casing 10b having an upper closure 11b andcontaining three pistons 25b, 33b and 35b together with their respectivedouble walls 30b and 36b and wall 41b. Ducts 27b and 59b throughrespective pistons 25b and 33b, provide for boom or shaft extension byuse of hydraulic fluid sent into the casing at fitting 52b. Fitting 6lbtogether with ducts 63b, 65b, 67b and 69b and double wall spaces 64b and68b serve for retraction in the manner previously explained inconnection with FIG. 1. Central conduit 28b fixed to upper closure 1 1bserves for delivery of material injected into the upper end of tube 28bwhich then is ejected through opening 45b through the lower closuremember 44b. O-ring-type guides 107 and 108 set in respective recessesaid in maintaining the position of tubular conduit 28 within cylinder32b.

From this description it is recognized that the boom arrangement may beextended and retracted as desired and in any position of extension orretraction material injected at the upper end of tube 28b will beejected out of opening 45b.

The devices according to this invention are capable of innumerable otheruses in addition to a drill rig mentioned above as one important use.For example, the extendible rotary boom or shaft may be used as a longdistance horizontally positioned drill with which a reservoir of wateror other drilling fluid may be used for injection of fluid through thematerial conduit to the drilling bit. Another use would be as a grindingor milling tool, in which case the shaft members would again be likelyto be placed positioned horizontally with provision for injectinglubricant through the material conduit to the working parts. Another usewould be to support another more or less similar multi-shaftarrangement, in which case one such device could be pointed upwardlywith provision for mounting the second multi-shaft device on the end ofthe outermost shaft section. Still another use could be as a firefighting boom in which water is supplied to the injector conduit systemand ejected from the boom at some distance from the position of supply.The boom may also be used as a fuel system in which fuel is supplied tothe materialconveying conduit and delivered at some distance within thelimits of extension of the boom. Still a further use is as a sybroneticspositioner.

As used in the specification, the terms such as tubular member orconduit member are used to cover such members whether they be ofcircular cross-section or square cross-section or some othercross-section, and the expression shaft covers a boom whether rotatableor not, and vice versa.

It will also be understood that any number of telescoping shaft membersand any number of telescoping material conveying conduit members may beused, as may be desired, and not merely the particular numbersillustrated in the drawings, which are for illustration rather than forlimitation of the invention.

It will be understood that the embodiments of the invention illustratedand described herein are given by way of illustration and not oflimitation, and that modifications or equivalents or alternatives withinthe scope of the invention may suggest themselves to those skilled inthe art. Thus although in FIGS. 1 and 7 three piston members are shownand in FIG. 4, two piston members are shown, it will be understood thatsome other number of piston members may be used without departing fromthe scope of the invention. Moreover, in a device having two or moreseparate material conveying con- 9 duits such as represented by FIG. 4,the materials may or may not be different and may or may not all flow inthe same direction.

I claim:

1. In an extendible and contractible shaft having a plurality of shaftmembers having a common longitudinal axis and each, except the outermostshaft member, being telescoped within the one next adjacent,

each telescoped shaft member having a piston slidably sealed to theinner wall of the next adjacent outer shaft member to form a series oftendemarranged sealed pistons,

closure means at the end of said outermost shaft member which thepistons approach when the shaft is contracting,

fluid passageways between adjacent shaft members,

means providing fluid communication between adjacent fluid passageways,

a first port means communicating with one side of said piston seals anda second port means communicating with the opposite side of said pistonseals, whereby application of fluid pressure at said first port meansextends the length of said shaft and application of fluid pressure atsaid second port means contracts the length of said shaft,

the improvement comprising:

material conveying conduit means comprising a first material conveyingtubular conduit section within said shaft and fixed relative to saidoutermost shaft member and communicating with the exterior of said shaftthrough said closure means,

a second material conveying tubular conduit section slidably sealed tosaid first material conveying conduit section so that the conduit meansis thereby extendible; and

opening means at the end of the shaft opposite the closure meansproviding communication with the conduit means.

2. A shaft according to claim 1 in which the second material conveyingconduit section is attached to. one of said pistons.

3. A shaft according to claim 1 in which a third material conveyingtubular conduit section is attached to a second of said pistons and isslidably sealed to the second material conveying conduit section,thereby making the conduit means further extendible.

4. A shaft according to claim 1 in which the first material conveyingconduit section comprises a tubular member concentric with thelongitudinal axis.

5. A shaft according to claim 1 in which the conduit means comprises anannular region between the first and second conduit sections concentricwith the axis.

6. A shaft according to claim 5 in which the annular region surroundssaid first conduit section.

7. A shaft according to claim 5 in which both of said conduit sectionsare fixed relative to said outermost shaft member.

8. A shaft according to claim 7 including a conduit member incommunication with said first conduit section and attached to one ofsaid pistons.

9. A shaft according to claim 1 which includes means for driving saidshaft members in rotation.

10. A shaft according to claim 5 which includes means for driving saidshaft members in rotation.

11. In an extendible and contractible shaft having a plurality of shaftmembers having a common longitudinal axis and each, except the outermostshaft member, being telescoped within the one next adjacent,

each telescoped shaft member having a piston slidably sealed to theinner wall of the next adjacent outer shaft member to form a series oftandemarranged sealed pistons,

closure means at the end of said outermost shaft member which thepistons approach when the shaft is contracting,

fluid passageways between adjacent shaft members,

means providing fluid communication between adjacent fluid passageways,

a first port means communicating with one side of said piston seals anda second port means communicating with the opposite side of said pistonseals, whereby application of fluid pressure at said first port meansextends the length of said shaft and application of fluid pressure atsaid second port means contracts the length of said shaft,

the improvement comprising:

first materialconveying conduit means comprising a first materialconveying tubular conduit section positioned to provide communicationfrom the exterior of said shaft through said closure means to a positionwithin said shaft, and fixed relative to said outermost shaft member,

a second material conveying tubular conduit section movablelongitudinally within said first conduit section and attached at its endopposite said closure means to a shaft member other than the outermostshaft member.

12. A shaft according to claim 11 in which said other shaft member isprovided at its end opposite said closure means, with a second closuremeans, said second closure means having an opening which communicateswith said second conduit section.

13. A shaft according to claim 12 in which a third material conveyingtubular conduit section is positioned between said first and secondconduit sections and is slidably related to both said first and secondconduit sections.

14. A shaft according to claim 11 which includes a second materialconveying conduit means comprising a tubular member providing an annularconduit surrounding said first material conveying conduit means andbeing fixed to the outermost shaft member, the annular conduitcommunicating with the exterior of the shaft through the first mentionedclosure means, said second closure means being provided with a secondopening providing communication with said annular conduit.

15. A shaft according to claim 14 in which a shaft member surroundingsaid tubular member moves longitudinally relative to said annularconduit to extend the length of said annular conduit.

1. In an extendible and contractible shaft having a plurality of shaftmembers having a common longitudinal axis and each, except the outermostshaft member, being telescoped within the one next adjacent, eachtelescoped shaft member having a piston slidably sealed to the innerwall of the next adjacent outer shaft member to form a series oftendem-arranged sealed pistons, closure means at the end of saidoutermost shaft member which the pistons approach when the shaft iscoNtracting, fluid passageways between adjacent shaft members, meansproviding fluid communication between adjacent fluid passageways, afirst port means communicating with one side of said piston seals and asecond port means communicating with the opposite side of said pistonseals, whereby application of fluid pressure at said first port meansextends the length of said shaft and application of fluid pressure atsaid second port means contracts the length of said shaft, theimprovement comprising: material conveying conduit means comprising afirst material conveying tubular conduit section within said shaft andfixed relative to said outermost shaft member and communicating with theexterior of said shaft through said closure means, a second materialconveying tubular conduit section slidably sealed to said first materialconveying conduit section so that the conduit means is therebyextendible; and opening means at the end of the shaft opposite theclosure means providing communication with the conduit means.
 2. A shaftaccording to claim 1 in which the second material conveying conduitsection is attached to one of said pistons.
 3. A shaft according toclaim 1 in which a third material conveying tubular conduit section isattached to a second of said pistons and is slidably sealed to thesecond material conveying conduit section, thereby making the conduitmeans further extendible.
 4. A shaft according to claim 1 in which thefirst material conveying conduit section comprises a tubular memberconcentric with the longitudinal axis.
 5. A shaft according to claim 1in which the conduit means comprises an annular region between the firstand second conduit sections concentric with the axis.
 6. A shaftaccording to claim 5 in which the annular region surrounds said firstconduit section.
 7. A shaft according to claim 5 in which both of saidconduit sections are fixed relative to said outermost shaft member.
 8. Ashaft according to claim 7 including a conduit member in communicationwith said first conduit section and attached to one of said pistons. 9.A shaft according to claim 1 which includes means for driving said shaftmembers in rotation.
 10. A shaft according to claim 5 which includesmeans for driving said shaft members in rotation.
 11. In an extendibleand contractible shaft having a plurality of shaft members having acommon longitudinal axis and each, except the outermost shaft member,being telescoped within the one next adjacent, each telescoped shaftmember having a piston slidably sealed to the inner wall of the nextadjacent outer shaft member to form a series of tandem-arranged sealedpistons, closure means at the end of said outermost shaft member whichthe pistons approach when the shaft is contracting, fluid passagewaysbetween adjacent shaft members, means providing fluid communicationbetween adjacent fluid passageways, a first port means communicatingwith one side of said piston seals and a second port means communicatingwith the opposite side of said piston seals, whereby application offluid pressure at said first port means extends the length of said shaftand application of fluid pressure at said second port means contractsthe length of said shaft, the improvement comprising: first materialconveying conduit means comprising a first material conveying tubularconduit section positioned to provide communication from the exterior ofsaid shaft through said closure means to a position within said shaft,and fixed relative to said outermost shaft member, a second materialconveying tubular conduit section movable longitudinally within saidfirst conduit section and attached at its end opposite said closuremeans to a shaft member other than the outermost shaft member.
 12. Ashaft according to claim 11 in which said other shaft member is providedat its end opposite said closure means, with a sEcond closure means,said second closure means having an opening which communicates with saidsecond conduit section.
 13. A shaft according to claim 12 in which athird material conveying tubular conduit section is positioned betweensaid first and second conduit sections and is slidably related to bothsaid first and second conduit sections.
 14. A shaft according to claim11 which includes a second material conveying conduit means comprising atubular member providing an annular conduit surrounding said firstmaterial conveying conduit means and being fixed to the outermost shaftmember, the annular conduit communicating with the exterior of the shaftthrough the first mentioned closure means, said second closure meansbeing provided with a second opening providing communication with saidannular conduit.
 15. A shaft according to claim 14 in which a shaftmember surrounding said tubular member moves longitudinally relative tosaid annular conduit to extend the length of said annular conduit.